Jump to content
  • Advertisement
Sign in to follow this  
3TATUK2

Parallax Occlusion Mapping

This topic is 2100 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Advertisement

i got it running without errors but the results are screwy :/ would be grateful for anyone else with another example

Share this post


Link to post
Share on other sites

i got it running without errors but the results are screwy :/ would be grateful for anyone else with another example

it has nothing to do with deferred rendering, I just used that for lighting. You need to make sure your generated tangent vector are ok, then I suppose after doing normal mapping this shouldn't be much challenge either. The directx sdk has a great example.

Share this post


Link to post
Share on other sites

so . . . it "kind of" works, but mainly up close from only one direction and far away it gets too distorted.. here's a vid, take a look (only the brick in the hallway[texture you supplied] is parallaxed)

 

 

Also, this is how I calculate my tangent stuff in the vertex shader:

 

vec3 c1 = cross( v_Normal, vec3( 0, 0, 1 ) );
vec3 c2 = cross( v_Normal, vec3( 0, 1, 0 ) );
vec3 tangent;
if( length( c1 ) > length( c2 ) ) tangent = normalize( c1 );
else tangent = normalize( c2 );
vec3 n = normalize( V_NormalMatrix * v_Normal );
vec3 t = normalize( V_NormalMatrix * tangent );
vec3 b = cross( n, t );
 
I see that which is probably basically what you have as your `vertex_output.tbn`
 
At first i thought `vs_to_ts` was the same as `vertex_output.tbn`, but apparently not... So i tried this instead:
 
mat3 vs_to_ts = mat3(t.x,b.x,n.x,t.y,b.y,n.y,t.z,b.z,n.z );
 
and these are the results I got. No distortion. . . but still seems somewhat wrong? It like... goes from one direction to the other, based on the direction i'm viewing it from..
 
 
It almost seems like my tangent calculations are wrong? But, I use them in my specular normalmapping which works perfectly fine, so I don't think they're off..

Share this post


Link to post
Share on other sites

Hmm, I just tried by implementing the one from this page, and I get basically the same results

 

http://www.gamedev.net/page/resources/_/technical/graphics-programming-and-theory/a-closer-look-at-parallax-occlusion-mapping-r3262

 

Maybe that's how it's supposed to be. Also might not be worth the performance hit

you quite possible have some problems with coordinate spaces or your tangents/normals etc. aren't good. it should look like this (look at the floor: stable, solid, great at grazing angles):



performance wise, it should be rougly the same speed as tessellation, but this doesn't have to be tweaked that much. So it IS worth the implementation (imho). It does have some performance impact but that should be ok.

Edited by Yours3!f

Share this post


Link to post
Share on other sites

 

so . . . it "kind of" works, but mainly up close from only one direction and far away it gets too distorted.. here's a vid, take a look (only the brick in the hallway[texture you supplied] is parallaxed)

 

 

Also, this is how I calculate my tangent stuff in the vertex shader:

 

vec3 c1 = cross( v_Normal, vec3( 0, 0, 1 ) );
vec3 c2 = cross( v_Normal, vec3( 0, 1, 0 ) );
vec3 tangent;
if( length( c1 ) > length( c2 ) ) tangent = normalize( c1 );
else tangent = normalize( c2 );
vec3 n = normalize( V_NormalMatrix * v_Normal );
vec3 t = normalize( V_NormalMatrix * tangent );
vec3 b = cross( n, t );
 
I see that which is probably basically what you have as your `vertex_output.tbn`
 
At first i thought `vs_to_ts` was the same as `vertex_output.tbn`, but apparently not... So i tried this instead:
 
mat3 vs_to_ts = mat3(t.x,b.x,n.x,t.y,b.y,n.y,t.z,b.z,n.z );
 
and these are the results I got. No distortion. . . but still seems somewhat wrong? It like... goes from one direction to the other, based on the direction i'm viewing it from..
 
 
It almost seems like my tangent calculations are wrong? But, I use them in my specular normalmapping which works perfectly fine, so I don't think they're off..

 

 

hey there, I only had time to look at this now, here's how I calculate the tangents (on the cpu):
https://github.com/Yours3lf/libmymath/blob/master/mymath/mm_util.h#L102

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

GameDev.net is your game development community. Create an account for your GameDev Portfolio and participate in the largest developer community in the games industry.

Sign me up!